i have no idea if this is already a thing or not but i think that if you have a wither it should stay within your island boundaries maybe also have a max height Smaller then the player's max height ( to build up to ) and also smaller then the player's limit that they can go down because they might roam into the void if the void is a few blocks away also ive heard stories about people's withers getting killed by expliots and maybe to counter this we could have it so that a player cant go within like 5 blocks of the wither except if its the one who summoned the wither also maybe have it so its virtually a shield around the wither so things cant go into the wither's " personal bubble" again except if its the summoner
I think everyone just didn’t know what to say I support it but maybe just the barriers of your island your not too clear in your explanation of it yes you can make withers 4 soul sand in any shape and 3 wither skulls. Try asking these type of questions on discord or some staff members profiles